Gas turbine unit having an axis parallel to the main gas flow, the gas turbine unit comprising: a blade having a tip; a stator heat shield having an inner surface facing the blade tip; wherein the inner surface of the stator heat shield and the blade tip define a variable clearance depending on the applied thermal condition; wherein the blade tip is configured to have a cylindrical shape along the axial direction in a hot running condition starting from a conical shape along the axial direction in a cold starting condition.

A gas turbine engine fuel nozzle comprises a spray tip defining a fuel exit passage therethrough that extends along a central axis. The fuel exit passage has an exit orifice aligned with the central axis. The exit orifice is circumscribed by an inner annular surface. The inner annular surface has a spherically-convex profile in cross-section, the profile being constant around the circumference of the inner annular surface.

A turbocharger is provided with an improved bearing which is formed as a floating ring bearing or a semi-floating ring bearing having a conical or hemispherical shape which supports both journal and thrust loads. The floating ring bearing may have conical floating ring bearings (70), (100), (180) that define inner and outer conical bearing surfaces (71), (108), (185) and (72), (109), (186) which cooperate on the inside with corresponding conical journals (75/76), (111/112), (187/188) that rotate with the shaft (53), and cooperate on the outside with a stationary bearing housing (52) to form inner and outer fluid films. Alternatively, the floating ring bearing may have a pair of hemispherical floating ring bearings (85), (140), (210) that have hemispherical inner and outer bearing surfaces (86), (144), (211) and (87), (145), (212) which form inner and outer fluid films. A semi-floating ring bearing may also be provided with these structures.

A method for servicing a gas turbine engine includes providing access from a forward section of the gas turbine engine to a gearbox contained within a bearing compartment.

A double frangible bearing support structure supports a low pressure rotor of an aircraft engine. The support structure has a first bearing assembly including a first bearing supported by a first bearing support adapted to buckle or frange when subject to a predetermined critical load resulting from an abnormal rotor imbalance. The support structure has a second bearing assembly comprising a second bearing having rolling elements disposed between inner and outer races. The outer race is connected to a second bearing support by means of frangible bolts adapted to fail when subject to a predetermined critical load resulting from radial displacements and loads of the low pressure rotor following decoupling/franging at the first bearing support.

A heat exchanger for a gas turbine engine includes a heat exchanger body having a first surface and a second surface oriented at least partially at an oblique angle relative to the first surface. The heat exchanger body defines a plenum extending between the first and second surfaces. Furthermore, the heat exchanger body defines a fluid passage extending through the second surface such that the fluid passage is in fluid communication with the plenum. The fluid passage, in turn, includes first and second portions. The first portion intersects the plenum at an intersection and defines a line of projection extending normal to the second surface. The second portion defines a line of projection extending normal to the first surface. The fluid passage further includes a curved portion extending from the first portion to the second portion.

A gas turbine engine article includes an article wall that defines a cavity, a cooling passage network embedded between inner and outer portions of the article wall, and at least one conical passage through at least a portion of the inner portion of the article wall. The cooling passage network has an inlet orifice through the inner portion of the article wall to receive cooling air from the cavity, an outlet orifice through the outer portion of the article wall, and an intermediate region of passages that connects the inlet orifice to the outlet orifice. The conical passage has a first end that is proximate the cavity and a second end that opens at the intermediate region of passages.

An apparatus for an impingement hole for an engine component of a gas turbine engine includes an impingement baffle. The impingement baffle is spaced from an impingement surface and includes a plurality of impingement holes for providing an impingement flow to the impingement surface. The impingement holes can have an angled upstream edge such that an inlet has a greater cross-sectional area than an outlet. The walls of the impingement holes can have a hood to provide a higher shear flow content to minimize dust accumulation on the impingement surface.

An apparatus and method for an engine component having a hot surface adjacent a hot combustion gas flow and a cooling surface adjacent a cooling fluid flow can include at least one dimple for enhancing the cooling along the cooling surface. The dimple can be shaped having a head and a tail with the head disposed upstream of the tail to provide for reduced dust collection along the engine component.

A heat exchanger for an aircraft engine includes: a body including a plate-like first member and a plate-like second member that are stacked in a thickness direction of the first and second members and joined together, and a channel which is defined in the body and in which the cooling target fluid flows; and a corrugated fin plate disposed in the channel in the body. The body is bent along a curved surface to which the heat exchanger is attached. A plurality of heat dissipation fins stand on an outer surface of at least one of the first member or the second member.